2.1. Experimental Design and Lay out
The experiment was set up in a completely randomized design (CRD) with three replications. The experimental treatments consisted of different seed priming techniques under various levels of salinity stress as below.
2.2. The Physical and Chemical Properties of the Soil
The soil samples (used in pot) were dried at room temperature mixed thoroughly, grinded, sieved with a 2 mm sieve and preserved in plastic containers for subsequent laboratory analysis. Bulk density was determined through volume basis. Texture, porosity and particle size were done though hydrometric, stochastic and sieving method, respectively. Particle size, bulk density, porosity and texture of the soil were 2.57, 1.42, 44.7 and silty loam, respectively. Chemical properties of soil like pH, OM, total-N, P, K and S were determined through glass electrode pH meter method, wet oxidation method, kjeldahl method, SnCl2 reduction method, NH4OAC method and turbidimetric method, respectively. The pH, OM and total N, K of the soil were slightly acidic (5.8), low (1.3) and low (0.101), low (0.12), respectively, while P, S, Zn, B were above critical limit.
2.3. Pot Preparation
The experiment was carried out in small plastic tray under natural light in the net house of the Department of Agronomy; BAU. The trays were filled by sand. The inert materials, visible insect pests and plant propagules were removed. Clean and dry plastic trays of 2 L were used for each treatment.
2.4. Salinity Development
Salt solution was prepared artificially by dissolving calculated amount of commercially available NaCl with tap water to make 0.25, 0.5 and 1.0 dS?m−1 NaCl solution. The salt solution was applied as per treatment specification. Similar moisture content of each tray was maintained by adding water every day.
2.5. Priming Techniques (Seed Priming)
Required number of maize seeds were soaked in distilled but cool water for 0 hours, hydro-priming 24 hours, hydro-priming 48 hours, halo-priming 48 hours (1% NaCl solution), osmo-priming 48 hours (2% sugar solution) at around room temperature as per treatments. After priming seeds in water then taken out and water at seed surface was wiped out. Twenty five seeds were sown in each tray for seedling emergence.
2.6. Fertilization
All fertilizers used (urea, TSP, MoP, Gypsum, Zinc sulphate and Boric acid) according to requirement on soil test basis using fertilizer recommendation guide 2005.
2.7. Data Collection and Analysis
The analysis of variance (ANOVA) for various crop characters and also were done following the principle of F-statistics. Mean comparison of the treatments were adjudged by the Duncan’s Multiple Range Test.